Offsetting mechanism



May 4, 1926. W.C.HENDER$ON OFFSE TTING MECHANISM 2 Sheets-Sheet 1 Filed June 14. 1922,

a tfozmug May 4 1926. 1,583,690

' w. c. HENPERSON OFFSETT'ING MECHANISM Filed June 14, 1922 2 Sheets-Sheet 2 gnucntoz Patented May 4, 1926.

WILLIAM c. nnnnnnson, or semi, ivrrssrsslrrr.

OFFS ETTING MECHANISM.

Application filed June 14, 1922. Serial No. 568,172

To all whom it may concern:

Be it known that WILLrAM G. Hannnnson, a citizen of the United States of America, residing at Bude, in the county of Franklin and State of Mississippi, has invented'new and useful Improvements in Oifsetting Mechanisms, of which the following is a specification. i

The object of the invention is to provide a simple and eflicient offsetting mechanism for saw mill carnages and similar structures as a means of providing'for. the return of the carriage 1n a path sufficientlyv offset from that pursued in its forward movement to avoid a drag of the saw on thecut surface of the log or of the timber; and with this object in view the invention consists in a construction and combinationuof parts of which a preferred embodiment is shown in the accompanying drawings, wherein Figure 1 is aplanview partly broken away of an off-setting mechanism embodying the invention applied in the operative positionto a saw mill carriage.

Figure 2 is a transverse section on the plane indicated by the line 2-2 of Figure 1.

Figure 3 is a section on the plane indicated by the line 3-8 of Figure 1.

Figure 4 is a detail view of the shoe.

Figure 5 is a similar view of the bellc-rank lever.

Figure 6 is a similar View of the rocker by which connection is made with the rock shaft.

Figures 7 and 8 are similar views respectively of the yoke and collar by which connection is made between the rock shaft and the wheel spindles. I

A conventional form of carriage is indicated at 10 provided with the front and rear rollers 11 and 12 of which the former are peripherally grooved as in the ordinary practice for traversing a V-guide bar or rail, said wheels being carried by spindles 13 extending transversely of the path of movement of the carriage with the bearings 1 1 of the latter adapted for movement longitudinally of the spindles to permit of a forward and rearward movement of the carriage relative to the wheels.

Disposed longitudinally of the carriage or parallel with the path of operative movement thereof, and mounted in suitable bearings 15 on the carriage is a rock shaft 16 provided near its extremities with yokes 17, each of which is provided with a sleeve 18 keyed to the rock shaft and having radial arms 19 carrying pins 20, which are terminally headed, as shown at 21 to engage seats 22 in a collar 23 which is secured to V the adjacent wheel spindle between retaining rings 2-1 which may be held in place by set screws or any equivalent means. The collar 23 is preferably split to facilitate its application to the spindle and therefore the rings 24 may be fastened upon or formed integral withthe spindle and as the vrock shaft is mounted in bearings secured to the carriage it is obvious that a rocking movement of the shaft willcause a forward and rearward movement of the carriage relative to the spindlesof the supporting wheels.

Theflpins 20 are preferably threadedand extend through suitable openings in the arms 19 andar e engaged by suitable nutsv to provide for relative adjustment.

A shoe 26 is arranged with a channeled bearing edge 27 to traverse the forward guide bar or track and exert a slight frictional resistance by reason'of such contact, the same having a limited movement longitudinally and independently of the carriage determined by upstandiiig fingers 28 operating in keepers 29 which are elongated in a direction'parallel with the path of the carriage and carried by a keeper plate 30 secured to the carriage, so that as the carriage reverses its direction of movement at the ends of its forward and rearward strokes the resistance between the shoe and the guide serves to hold the shoe stationary while the carriage moves independently thereof for a distance determined by the length of the keepers.

Also mounted upon the carriage at a pivotal point 81 is a bell-crank lever 32 having connection with the shoe at one end and having connection at the other end with the rock shaft so that "the independent movement of the shoe relative to the carriage serves to actuate the bell-crank lever and thereby communicate a limited rocking movement to the shaft 16 to thereby shift the carriage rcarwardly or forwardly according to the direction of movement of the carriage in itspath. The connection illustrated in thedrawings between the bellcranlclever and theshoe consists of a pin arranged in spanning relation with a slot 34k in the shoe for engagement by a notch 35 in the end of the transverse arm of the bell-crank lever, and the connection between the other or the longitudinal arm of said lever and the rock shaft consists of arocker 36 carried by the rock shaft and a link 37 extending from an arm 38 of the rocker to said longitudinal arm 32 of the bell-crank lever. In practice it is preferred to provide the link with a means of adjustment such as the turn buckle 39so that a relative adjustment of the rock shaft angularly with respect to the bell-crank lever may be effected to insure a proper and sufficient movement of the carriagewith relation to the spindles of the bearing rolls. The rocker 36 in addition to the arm 38 includes a sleeve 40 which is keyed to the shaft, and the bell-crank lever is mounted upon a plate 41 from which extends the stud 81 forming; the fulcrum of said lever.

In operation, as Will be obvious, the transverse movement of the carriage due to the drag of the-shoe and the communication of motion through the bell-crank lever to the rock shaft Will occur at each end of the longitudinal path of movement of the carriage, so as to offset the saw or other tool load in the operation of the mechanism While insuring a reliability in action Which is desirable in connection With mechanisms of this type.

Having described the invention, What is claimed asnevv and useful is An offsetting mechanism for a roller supported carriage having a longitudinally disposed rock shaft provided with means for effecting atransverse movement of the earriage With reference to its supporting roller, a drag for traversing and frictionally engaging one of the guides of the carriage, and spaced keepers'mounted on the site of the carriage and elongated in the direction of the length of the carriage, the drag having; lingers engageable in said keepers tll'lCl'il'lOVQbl' longitudinally thereof, and a hell crank lever pivoted on the under side of the carriaqe and having an operative connection with the rock shaft comprising a link connected with the shorter arm of the bell crank lever, the longer armof said bell WILLIAM C. HENDERSON. 

